Make the "wave" edge effect for SnagIt for Mac like that in SnagIt for Windows

I'm using SnagIt 2018 for Mac, and while I love your software and have been using it for Windows for a long time, there is one thing that I sadly dislike when using SnagIt on Mac.

The wave edge effect looks completely wonky on the Mac. While one is able to create a "long" wave effect - e.g. one or two ripples on the edge of a relatively long image - this is impossible on a Mac; the end result looks like something a toddler would make, which is not the effect that I'm aiming for.

Here is a SnagIt-for-Mac example:

My SnagIt-using Windows-based friends all laugh at me.

Here's an example of a smooth wave effect on Windows:

Is it possible to achieve the same level of wave edge making as on Windows, with my Mac?

Sadly, that's the initial problem; the wave does not look anything like it does on Windows. This is what I described in my original post, with screenshots included. TechSmith has already accepted this, and will hopefully implement a fix soon.